With the development of smart power meters, it will now be possible for power companies to charge consumers at different rates during the day. They are also now pushing for AC to DC convertors to have a high power factor. A perfect power factor is that of a resistor. Using an efficient bidirectional power converter could start making economical sense if the power companies begin charging a high enough rate difference over the day. It might some day make economic sense to store energy in batteries at home during low rates, and then convert the energy back to AC during high rates. And the battery energy gets transferred to the AC line as a high power factor negative resistor, not as an AC inverter. Not very many bidirectional AC to DC converters work with a perfect power factor and without the use of diodes as rectifiers. And at low AC voltages, diode rectifiers cut into power efficiency.